TSHong

I finally have repaired my trunk to 100% operational and hopefully for the long haul. When I got my first D3, a MY 2005 W12 and I would have to help the trunk open every time. With research here on the board, consensus was mostly due to a weak motor. The dealer always want you to replace the hinges too but I decided just to replace the motor with the newer metal bodied one. Had my tech replace it and it literally took 15 minutes to install. So my trunk worked 100% for about a little more than a year. Then it would not open sometimes, especially if I did not use it for several days. I always kept my hinges lubricated and tested my trunk struts per Audi.

I totaled my 05 W12 and got my current 09 W12 a little over a year ago and the trunk worked 100%. It had the updated hinges and the motor so I thought I was good. But this summer I noticed it worked most of the time but sometimes the dreaded partial lift and then drop and lock appeared its ugly head. I isolated the symptom that on summer days where it gets to near 100 degrees here in GA, the first time opening would always fail to open. If the temp was cool, it would open 100%. I felt the struts on a hot day and they get really hot. I was thinking if your struts get weak, the higher temp would lower the pressure. I watched the trunk and the right side would lift while the left was slower to lift. Louis noticed this on his trunk so he went the route to use helper springs.

A few of the members here have bought new struts and it help them solve the problem. I was skeptical on theory because it seems like the struts would not help until the trunk started moving up some and the problem is the initial start. I decided to go ahead with replacing the strut since we can get Stabilus for $77 delivered to your door on eBay. I ordered them and they sent me two struts with numbers SG301045 and SG301046. Went to their website, the part 45 has 87.68 PSI and part 46 has 59.58 so I installed the 45 on my left side and the 46 on my right side. I'm glad I did because now it works 100% of the time. Let me say that the struts make a huge difference. I can tell you that the trunk pops open and accelerates instantly to the opening speed. With the old struts, it unlatch and it would take a second or two to accelerate to the constant opening speed. With the the new struts, it unlatches and is instantly at opening opening speed.

After going though replacing the motor and the struts, I think the struts replacement would help more people. I think the struts would help a weaker motor. Our D3 issue is the initial clutch engagement and with new struts helps that the most. I never thought the struts would make so much difference but it really does. Hope this helps answer some questions about a problem that we all will go through.

NOR_KNet

Thanks for the info TSHong Ill remember this when my trunk will start failing

Btw.. you have a video of your new struts installed so we can see how then now operate? (if its possible to see the difference though)

Regards
Kenneth

Turbo Tony

Useful post, thanks. I'd love to see a video too.

MainelyA8

Good info. I recently found that one of my hinges is bent, and haven't been able to bend it back into place. Not sure if it's that, or the motor dying, but it seems to have been struggling to open lately.

TSHong

Here is a quick video I shot today. It was late this afternoon and only got up to about 89 degrees today but still hot.

I did not think to take a video before because I had no idea that the struts would make so much a difference. I already have disposed of the old struts so no previous video unfortunately.

dvs_dave

Good info. Like you I was skeptical that the struts would make any difference, but seems I was wrong. I have the new style metal trunk motor and am keen to keep it operating nicely if I can so will probably pick up a set soon.

TSHong

I was really surprised myself at the results of the different component changes. Like you said, I think it will help keep the clutch in the motor over the long haul.

Tstealth32

I also have the upgraded motor. Trunk was struggling to open and would slam shut when reaching half way down. Bought new struts right away, and now it opens and closes smoothly and quietly.

Turbo Tony

I have the new motor and it's nowhere near as quick or smooth as that!

I've made enquiries to get my struts re-gassed. As soon as my car gets back to me, I'll be getting them done.

TSHong

I would buy new ones since they are pretty cheap here in the US, not sure what international shipping would be. I would only re-gas them if they can pressurize them with factory specs. The left side has more pressure since the motor is tied to the right side.